title: A mussel tissue certified reference material for multiple phycotoxins. Part 3: homogeneity and stability.
abstract: A candidate certified reference material (CRM) for multiple shellfish toxins (domoic acid, okadaic acid and dinophysistoxins, pectenotoxins, yessotoxin, azaspiracids and spirolides) has been prepared as a freeze-dried powder from mussel tissues (Mytilus edulis). Along with the certified values, the most important characteristics for a reference material to be fit-for-purpose are homogeneity and stability. Acceptable between-bottle homogeneity was found for this CRM. Within-bottle homogeneity was assessed using domoic acid, and it was shown that repeated subsampling of the CRM can be performed precisely down to 0.35 g. Both short- and long-term stability studies carried out under isochronous conditions demonstrated excellent stability of the various toxins present in the material. While degradation of some analytes was observed at +60°C in short-term studies, it was determined that shipping at ambient temperature is adequate. No instability was detected in long-term stability studies, and it was shown that the material can be held at +18°C safely for up to 1 year. To guarantee stability of the CRM over its lifetime the stock will be maintained at -20°C. The results of the homogeneity and stability testing show that CRM-FDMT1 is appropriate for its intended use in quality assurance and quality control of shellfish toxin analysis methods.
authors.affiliation: National Research Council Canada, Institute for Marine Biosciences, Halifax, NS, Canada. pearse.mccarron@nrc-cnrc.gc.ca
authors.forename: Pearse
authors.initials: P
authors.lastname: McCarron
authors.forename: Håkan
authors.initials: H
authors.lastname: Emteborg
authors.forename: Sabrina D
authors.initials: SD
authors.lastname: Giddings
authors.forename: Elliott
authors.initials: E
authors.lastname: Wright
authors.forename: Michael A
authors.initials: MA
authors.lastname: Quilliam
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000592:standards; D005612:Freeze Drying; D006358:Hot Temperature; D007608:Kainic Acid / Q000031:analogs & derivatives / Q000032:analysis; D008387:Marine Toxins / Q000032:analysis*; D013058:Mass Spectrometry / Q000592:standards*; D012015:Reference Standards
chemical_list: D008387:Marine Toxins; C012301:domoic acid; D007608:Kainic Acid